The BF3-catalyzed decomposition of m- and p-substituted α-diazoacetophenones in excess of methyl thiocyanate and ethyl thiocyanate gave the corresponding 2-methylthio-, and 2-ethylthio-5-aryloxazoles, respectively in good yields along with s-alkyl-n-aroylmethylthiocarbamates and α-ethoxyacetophenones. However, yields of 2-dimethylamino-5-aryloxazoles by the reaction of dimethylcyanamide with α-diazoacetophenones
A New and Mild Heterogeneous Catalytic Decomposition of α-Diazo Carbonyl Compounds Using Montmorillonite or Zeolite
作者:Sengodagounder Muthusamy、Srinivasarao Arulananda Babu、Chidambaram Gunanathan、Raksh Vir Jasra
DOI:10.1055/s-2002-20452
日期:——
A very mild method of decomposition of various α-diazo carbonyl compounds 1 in the presence of environmentally attractive solid acids such as montmorillonite K-10 or zeolite H-Y in a heterogeneous manner to furnish α-hydroxy/alkoxy ketones in very good yield is reported. Interestingly, novel bicycloalkane-1,3-diones and 3-furanones were obtained as unusual products in the case of aliphatic/alicyclic α-diazo carbonyl compounds.
Direct Synthesis of α-Alkoxy Ketones by Oxidative C-O Bond Formation
作者:Hui Yu、Yilan Xu、Yan Fang、Rui Dong
DOI:10.1002/ejoc.201600723
日期:2016.11
convenient method to prepare α-alkoxy ketones has been developed by oxidative coupling of aryl methyl ketones and alcohols. With aqueous tert-butyl hydroperoxide (6.0 equiv.) as the oxidant, tetrabutylammonium iodide (20 mol-%) as the catalyst, and TsNHNH2 (1.0 equiv.) as the additive, ketones underwent direct alkoxylation to give α-methoxy or α-ethoxy ketones in moderate to good yields.
Flexible Stereoselective Functionalizations of Ketones through Umpolung with Hypervalent Iodine Reagents
作者:Pushpak Mizar、Thomas Wirth
DOI:10.1002/anie.201400405
日期:2014.6.2
The functionalization of carbonyl compounds in the α‐position has gathered much attention as a synthetic route because of the wide biological importance of such products. Through polarity reversal, or “umpolung”, we show here that typical nucleophiles, such as oxygen, nitrogen, and even carbon nucleophiles, can be used for addition reactions after tethering them to enol ethers. Our findings allow novel